Warmer weather is here, which means so are horror stories about schools sending teen girls home for daring to reveal a bra strap, bare midriff, or shoulders. But some Ontario teens are fighting back.

Today is #CropTopDay, a movement started by a Toronto high school student named Alexi Halket.

In an event page on Facebook, Halket wrote that a male teacher at Etobicoke School of the Arts complained that a shirt she was wearing one day looked "too much like a sports bra."

"I went in to the office and refused to change or cover up, and I was sent to the principal where we talked for over an hour and came to no conclusion except a threat that if I wore something like this again I would be called in to the office," she wrote.

In response, Halket declared Tuesday — her birthday — crop top day.

Courtesy of Kyrstyn Kumor

"So PLEASE wear a crop top, sports bra, bralette, bandeau, or anything similar and stand in solidarity against the sexualization of women's bodies on my birthday," she wrote on Facebook.

And her fellow students responded. Both girls and guys showed up to school proudly wearing crop tops, some with messages of solidarity written on their skin.